The Experts below are selected from a list of 465210 Experts worldwide ranked by ideXlab platform
Zhaocheng Wang - One of the best experts on this subject based on the ideXlab platform.
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Non-orthogonal multiple access for 5G: Solutions, challenges, opportunities, and future Research Trends
IEEE Communications Magazine, 2015Co-Authors: Linglong Dai, Bichai Wang, Yifei Yuan, Zhaocheng WangAbstract:The increasing demand of mobile Internet and the Internet of Things poses challenging requirements for 5G wireless communications, such as high spectral efficiency and massive connectivity. In this article, a promising technology, non-orthogonal multiple access (NOMA), is discussed, which can address some of these challenges for 5G. Different from conventional orthogonal multiple access technologies, NOMA can accommodate much more users via nonorthogonal resource allocation. We divide existing dominant NOMA schemes into two categories: power-domain multiplexing and code-domain multiplexing, and the corresponding schemes include power-domain NOMA, multiple access with low-density spreading, sparse code multiple access, multi-user shared access, pattern division multiple access, and so on. We discuss their principles, key features, and pros/cons, and then provide a comprehensive comparison of these solutions from the perspective of spectral efficiency, system performance, receiver complexity, and so on. In addition, challenges, opportunities, and future Research Trends for NOMA design are highlighted to provide some insight on the potential future work for Researchers in this field. Finally, to leverage different multiple access schemes including both conventional OMA and new NOMA, we propose the concept of software defined multiple access (SoDeMA), which enables adaptive configuration of available multiple access schemes to support diverse services and applications in future 5G networks.
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next generation digital television terrestrial broadcasting systems key technologies and Research Trends
IEEE Communications Magazine, 2012Co-Authors: Linglong Dai, Zhaocheng Wang, Zhixing YangAbstract:In the last two decades, digital television terrestrial broadcasting (DTTB) systems have been deployed worldwide. With the approval of the fourth DTTB standard called Digital Television/ Terrestrial Multimedia Broadcasting (DTMB) by International Telecommunications Union (ITU) in December 2011, the Research on first-generation DTTB standards is coming to an end. Recently, with the rapid progress of advanced signal processing technologies, nextgeneration DTTB systems like Digital Video Broadcasting-Terrestrial-Second Generation (DVB-T2) have been extensively studied and developed to provide more types of services with higher spectral efficiency and better performance. This article starts from the brief review of the first-generation DTTB standards and the current status of emerging second-generation DTTB systems, then focuses on the common key technologies behind them instead of describing the specific techniques adopted by various standards. The state-of-the-art, technical challenges, and the most recent achievements in the field are addressed. The future Research Trends are discussed as well. In addition, the scheme of integrating DTTB and Internet is proposed to solve the crucial problem of information expansion.
Yuksel Goktas - One of the best experts on this subject based on the ideXlab platform.
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educational technology Research Trends from 2002 to 2014
Scientometrics, 2015Co-Authors: Ozlem Baydas, Sevda Kucuk, Melike Aydemir, Rabia Meryem Yilmaz, Yuksel GoktasAbstract:This study examined subject and Research method Trends in educational technology field from 2002 to 2014. Content analysis was applied in order to analyze 1255 articles published in BJET and ETR&D journals using the Educational Technology Papers Classification Form. According to the results, learning approaches/theories and learning environments were the subject most preferred by Researchers. The most commonly used Research methods were quantitative, qualitative, other (review or meta-analysis), and mixed method, in that order. Researchers tended to use questionnaires, documents, and interviews as data collection tools. The most commonly preferred sample type was the purposive sample, and undergraduate students were the most commonly chosen sample group, with the most common sample size being groups of 31---100. Frequencies, percentages, and tables were the most common presentation format for data in quantitative studies, while qualitative studies most often employed content analysis.
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educational technology Research Trends in turkey a content analysis of the 2000 2009 decade
Kuram Ve Uygulamada Egitim Bilimleri, 2012Co-Authors: Yuksel Goktas, Sevda Kucuk, Melike Aydemir, Gurkan Yildirim, Omer Arpacik, Esra Telli, Ilknur ReisogluAbstract:Abstract The purpose of this study is to examine Turkish educational technology studies in the academic literature within the scope of SSCI, and to reveal methodological Trends within these studies. For this purpose, 460 Turkeyaddressed articles, published between the years of 2000-2009 in 32 international journals, within the scope of 2010 SSCI were collected as data through ETPCF. The data were examined via content analysis and presented using descriptive statistical methods. According to the results, "educational environments" and "technology" were the topics mostly focused on in the articles. Regarding the Research methods, quantitative analysis was generally used in these studies. Questionnaires were used as a data collection tool, and convenience sampling methods were also used widely. Descriptive analyses were mainly preferred as a data analysis method. The results coming out of this study will be helpful for directing the future studies. Key Words Educational Technology, Instructional Technology, Research Trends, Publication Classification. Educational technologies, which emerge as innovative solutions to the question, "How can I learn more effectively?" change as a result of external factors on a day to day basis. Researchers have conducted numerous studies on the effects of these changes for students, teachers, learning environments and learning processes. Their Researches take a variety of studies, depending on the narrower focus within the field of education. But in order to direct future Research, determining the kinds of studies, which are still needed, is also important. Therefore, this study will review recent Turkey-addressed educational technologies articles, which were published in international journals, to take note of both their topics of Research and to find out the potential topics that need further studies. Trends of educational technology have drawn the attention of many Researchers from around the world (Caffarella, 1999; Costa, 2007; Hew, Kale, & Kim, 2007; Hranstinski & Keller, 2007; Klein, 1997; Latchem, 2006; Ma, 2000; Masood, 2004; Mihalca & Miclea, 2007; Ross, Morrison, & Lowther, 2010). The Researchers themselves typically determine which topics to focus on, which Research methods are best suited to their topics, which data to collect, how to select samples, and how to perform statistical analyses. All current tendencies in the field are a result of the precedents and Trends that earlier Researchers set as they worked out these elements in their studies. Some Researchers examined a considerable number of the Trends in the field of educational technologies. For instance, focus on journals of Klein (1997), Masood (2004), Hew et al., (2007), Ross et al., (2010) Educational Technology Research and Development (ETRD Hranstinski and Keller (2007) Computers & Education, Educational Media International, Journal of Educational Computing Research and Journal of Educational Media; Latchem (2006) British Journal of Educational Technology (BJET) were examined. As a result of the conducted analysis, it was found out that most of studies in educational technology are concentrated on media Research, computer based and computer aided instruction, learning psychology, distribution systems, instructional development, instructional methods, and instructional design. Once experimental methods were often employed, but recently, qualitative methods have been increasingly used. The contributing authors of ETRD Costa, 2007; Ma, 2000). Computer-based and computer-aided instruction topics are generally the focus of these, and quantitative Research methods are employed in most of these studies. But recently, qualitative studies have been increasing while experimental studies have been considered important. …
Linglong Dai - One of the best experts on this subject based on the ideXlab platform.
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Non-orthogonal multiple access for 5G: Solutions, challenges, opportunities, and future Research Trends
IEEE Communications Magazine, 2015Co-Authors: Linglong Dai, Bichai Wang, Yifei Yuan, Zhaocheng WangAbstract:The increasing demand of mobile Internet and the Internet of Things poses challenging requirements for 5G wireless communications, such as high spectral efficiency and massive connectivity. In this article, a promising technology, non-orthogonal multiple access (NOMA), is discussed, which can address some of these challenges for 5G. Different from conventional orthogonal multiple access technologies, NOMA can accommodate much more users via nonorthogonal resource allocation. We divide existing dominant NOMA schemes into two categories: power-domain multiplexing and code-domain multiplexing, and the corresponding schemes include power-domain NOMA, multiple access with low-density spreading, sparse code multiple access, multi-user shared access, pattern division multiple access, and so on. We discuss their principles, key features, and pros/cons, and then provide a comprehensive comparison of these solutions from the perspective of spectral efficiency, system performance, receiver complexity, and so on. In addition, challenges, opportunities, and future Research Trends for NOMA design are highlighted to provide some insight on the potential future work for Researchers in this field. Finally, to leverage different multiple access schemes including both conventional OMA and new NOMA, we propose the concept of software defined multiple access (SoDeMA), which enables adaptive configuration of available multiple access schemes to support diverse services and applications in future 5G networks.
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next generation digital television terrestrial broadcasting systems key technologies and Research Trends
IEEE Communications Magazine, 2012Co-Authors: Linglong Dai, Zhaocheng Wang, Zhixing YangAbstract:In the last two decades, digital television terrestrial broadcasting (DTTB) systems have been deployed worldwide. With the approval of the fourth DTTB standard called Digital Television/ Terrestrial Multimedia Broadcasting (DTMB) by International Telecommunications Union (ITU) in December 2011, the Research on first-generation DTTB standards is coming to an end. Recently, with the rapid progress of advanced signal processing technologies, nextgeneration DTTB systems like Digital Video Broadcasting-Terrestrial-Second Generation (DVB-T2) have been extensively studied and developed to provide more types of services with higher spectral efficiency and better performance. This article starts from the brief review of the first-generation DTTB standards and the current status of emerging second-generation DTTB systems, then focuses on the common key technologies behind them instead of describing the specific techniques adopted by various standards. The state-of-the-art, technical challenges, and the most recent achievements in the field are addressed. The future Research Trends are discussed as well. In addition, the scheme of integrating DTTB and Internet is proposed to solve the crucial problem of information expansion.
G Vijaya S Raghavan - One of the best experts on this subject based on the ideXlab platform.
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bibliometric analysis of global Research Trends on microbial fuel cells using scopus database
Biochemical Engineering Journal, 2018Co-Authors: Jauharah Md Khudzari, Jiby Kurian, B Tartakovsky, G Vijaya S RaghavanAbstract:Abstract The rising demand for sustainable energy and the availability of abundant wastes have stimulated Research efforts around the world. As a newly emerging energy-based technology, microbial fuel cell (MFC) has received a significant attention due to its broad range of applications. Therefore, understanding the topics of interest and broadening collaboration networks are necessary to advance the Research development towards integrated efforts. In this bibliometric study, our aim was to evaluate the global Research Trends in MFC area based on publication outputs, co-authorships among authors and affiliated countries, and co-occurrences of author keywords. Using the Scopus database, a total of 4126 journal articles published between 1962–2017 were retrieved. Results have shown that since 2008, the number of publications increased by 100 articles every two years, resulting in the steady increase in the cumulative total publications until present. About 60% of the global total publications were contributed by Researchers from China and USA, leading the other 70 countries/territories. Also, among the most productive university from each of the 15 leading countries, four were amongst the world’s top 100 universities. In conclusion, recent progress in MFC Research includes the following (but not limited to) (i) electrode materials incorporated nanotechnology, ceramic, and biochar; (ii) mathematical modeling (e.g. artificial neural network); and (iii) economic assessment and life cycle analysis.
Yingkuan Wang - One of the best experts on this subject based on the ideXlab platform.
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Global Research Trends in food safety in agriculture and industry from 1991 to 2018: A data-driven analysis
Trends in Food Science and Technology, 2019Co-Authors: Kai Hu, Bin Li, Seyed Mohammad Taghi Gharibzahedi, Ye Su, Yongnian Jiang, Yingkuan WangAbstract:Abstract Food safety (FS), as a topic important to human health and wellbeing, has attracted a great deal of attention. With the large volume of publications in the area, it is hard to gain a comprehensive picture of the Research Trends. A scientometric data-driven analysis of the field can help reveal the diverse facets of FS. Food safety is critical in two important stages of the food system: food production and food processing, which are categorized as agriculture food safety (Agric-FS) and industry food safety (Ind-FS), respectively. In this work, these two closely-related but different Research fields are comparatively analyzed. Based on scientometric theory and metrics, characteristics of both fields are discussed in terms of annual Research output, active journals, important authors, and countries of activities. The overall output of publications is in an upward trend and the dynamics of publications in the two areas are in a similar pattern. Food Control and Journal of Food Protection are both representative journals for Agric-FS and Ind-FS. Jacxsens L, Uyttendaele M, LeJeune J, and Luning P are representative authors for Agric-FS and Jacxsens L, Griffith CJ, Luning P, and Uyttendaele M are representative authors for Ind-FS. The USA is the leading country in both fields by volume of output, followed by the UK and China. The Research focus areas over time are extracted by temporal co-word and co-citation analysis. It was found that the Agric-FS domain is more unevenly distributed. Early studies in Agric-FS topics have divergent directions because of divergent fresh produce. Important topics in later times are focused on foodborne disease and supply chains that support the fresh produce. In contrast, the Ind-FS focus has more focal topics, and the Research is concentrated on theories, tools, and practical issues in food quality and safety. Control methods such as HACCP are the focuses of early Research in Ind-FS. More practical issues concerning barriers for quality controls are studied in later periods, including human-related problems in business activities.
